Apple’s iOS handset sales are mainly generated from from one new model per year, although older models also contribute. Android sales are derived from a vast number of different phones using Google’s platform.

The U.S. is poised, however, to see these two companies go head to head. It’s expected that Apple will announce and release a new iPhone in August or September. Samsung introduced the Galaxy S 2 in May, spreading availability to many countries outside of the U.S. and claims 5 million sales in just 85 days.

Several U.S. versions of the Galaxy S 2, varying by carrier, are likely to launch within the next month or two, including at least one for AT&T that may have a hardware keyboard. AT&T accounted for more than 17 percent of all iPhone sales last quarter, so that particular battleground should prove interesting.

At 6.5 ounces, the phone is heavier than most smartphones, but the main reason is due to the 4-row QWERTY keyboard that hides under the 3.7-inch display. A 1.2 GHz dual-core chip keeps the phone moving along quickly and the wide aperture 8 megapixel camera is paired with smart software that supports a fast burst mode, HDR images and wide panoramic views.